The Special Edition DLC Add-on for Mark of the Ninja has 8 achievements.
Complete one of the original Mark of the Ninja levels using the Path of Wisdom.
Stun an elite guard with moths then dispatch him.
Disable a spotlight using the Dusk Moths.
Complete the new Special Edition level.
Dispatch two enemies at once using a body infected with Toxic Fungus.
Knock out an enemy again that was revived from being knocked out.
View any of the developer commentaries.
Read one of the history lesson developer commentaries.